Form clamp



DEC. 19, c T WALKER FORM CLAMP Filed Aug. 14, 1951 [NYE/V7072 Patented Dec. 19, 1933 FORM CLAMP Cass '1. Walker, San Jose, Calif., assignor to Barnes Corning Company; San Francisco,

Calif. 7

Application August 14,

11 Claims.

This invention relates particularly to form clamps for use in the construction of concrete walls.

It is one object of the present invention to provide an'improved clamping device which combines in the one structure both the means for effecting the clamping operation and the means for locking the device against dislodgement fro its finally clamped position.

g It is another object to provide a means of the character indicated that will besimple in form and construction, economical to manufacture, strong, durable, quickly and easily applied and removed, and highly efficientin its practical application.

In the accompanying drawing: Figure 1 is a sectional view through aportio of a concrete wall form with the clamp in opera tive position. V

Figure 2 is a'perspective view showing the working side of the revoluble part of the clamp.

Figure 3 is a perspective view showing the working side of the fixed portion of the clamp.

In the embodiment of the invention as herein disclosed, I show at 11 the side walls of a portion of a form for concrete material with the vertical'members at 22 and the outer horizontal purlines at 3-3.

In the present disclosure I show my'improved clamps as applied to a tie strap 4 having fingers as at 5 turned at right angles thereto to form positive spacing means for the said wal1s"11, the strap projecting through and beyond the said walls and having holes as at 6 formed therein adjacent its ends.

The clamp itself is built up of three parts, a plate '7 adapted to seat against the outer surface of the purline 3 and having projections 8 formed thereon to seat in the purline to prevent rotation of the plate; a rotatable head member 9 provided with a handle 10, and a rod 11 having a head 12 on its outer end, the said rod extending through holes 12 and 13 provided at the centers of plate 7 and head 9 respectively, and terminating in a hook 14 on its inner end.

The outwardly disposed working face of plate 7 is provided with an annular boss 15 having two similarly inclined, annular and parallel surfaces 16 and 17 thereon which lie at right angles to the axis of the boss and in concentric relation thereto, the said surface 1'? being positioned inside the surface 16. Each surface starts at the level of the plate and gradually rises to a given height in any one complete revolution, the highest point 16a of the'inclined surface 16 being 1931. Serial No. 557,139

positioned opposite the highest point 17a of the inclined surface 1'7, and the lowest points 16b and 17b of said surfaces being also positioned opposite each other.

At the end 16a of surface 16 is formed a stop The head member 9 is complementary to boss 15 and is provided with surfaces 19 and 20 with gradually inclined high and low points 19a--20a and 19b-20b respectively, identical with the corresponding parts onboss 15, the end 19a of part 19 having a stop 21 formed thereon which is adapted to engage stop 18.

In using the clamp the strap 4 is first placed in its proper position and then the rod 11 is hooked into the hole 6 in the strap, with the plate 7 seated, against the outer side of the purline as shown in Figure 1, and the opposing inclinedsuriaces 16,19 and 17, 20, positioned in intimate contact throughout their-lengths. By

rotating member 9 in the direction indicated by the arrow in Fig. 1, it will be forced to ride up on the inclined surfaces thereby drawing the .form into line and holding it rigidly until the head 9 is rotated in the opposite direction preparatory to removing the device.

By providing the double arrangement of inclined surfaces as 16 and 1'7, the one advanced one-hundred-and-eighty degrees beyond the other, a solid and balanced support is provided 55 for the head 9 and the said head is maintained at right-angles to rod 11 at all times regardless of the pressures applied. The stops 18 and 21 are so arranged that the head 9 cannot be turned -more than one complete revolution since such an operation would, of course, release the clamp.

This clamp may be applied and operated by one, man, and is so economical to manufacture that the great number used upon one large building representsno great investment, and no special tightener or other tool is required because the device functions both as tightener and holding clamp. The clamps may be quickly and easily recovered and used again and again.

In order to prevent slipping of head 9 on boss T 15 when the clamp is in use the opposing surfaces inclined of the two members are provided with corrugations 22. The said corrguations of the opposing inclined surfaces, being in engagement with each other when the clamp is in use. normally prevent the slipping or dislodgement of the head 9 with reference to the fixed plate '7.

It is to be understood, of course, that while I have herein shown and described but one specific embodiment of the invention, changes in form, '110 construction, and method of assembly and operation may be made within the scope of the appended claims.

I claim:

1. A cam structure of the character described comprising a pair of relatively revolvable cam members, the opposing faces of said cam members having complementary engaging portions formed thereon, each portion having a plurality of inclined annular surfaces formed thereon, the said surfaces of each portion being positioned one inside the other.

2. A clamp of the kind described comprising a normally fixed member having a plurality of gradually inclined and annularly disposed projections thereon, a rotatable member having a plurality of gradually inclined and annularly disposed projections thereon, the projections of one of the members being in operative engagement with the projections of the other member, and a tension rod extending through the members having a flared head at one end;

3. A clamp of the kind described comprising a normally fixed member having a plurality of gradually inclined and annularly disposed projections thereon, the said projections being provided with corrugated surfaces thereon, a rotatable member having a plurality of gradually inclined and annularly disposed projections thereon, the said projections being provided with corrugated surfaces which normally engage with the surfaces of the fixed member, and a tension rod extending through the members hav ing a flared head on one of its ends.

4. A clamp of the kind described comprising a normally fixed member having an annularly disposed projection thereon, a rotatable member having an annularly disposed projection thereon, the ends of the said projections being contiguous, a tension rod extending through the members having a head normally contacting with the rotatable member, and an operating handle secured to the rotatable member.

5. A clamp of the kind described comprising a normally fixed member having an annularly disposed projection thereon, a rotatable member having an annularly disposed projection thereon, the said projections having roughened sur faces normally contacting with one another, tension means extending through the members, and separate means for rotating the rotatable membet.

6. A clamping device of the kind described comprising a fixed member having a curved cam like surface which extends through an angle greater than ninety degrees, a rotatable member having a cam like surface adapted to contact with the cam like surface of the fixed member, a tension rod extending through openings provided at the axes of the members, having means at one end for fastening the rod to a device and a head at its opposite end.

7. A clamping device of the kind described comprising a fixed member having a curved and roughened cam like surface thereon, a rotatable member having a similarly curved and roughened cam like surface adapted to contact with the cam like surface of the fixed member, a tension rod extending through the axes of the members, and means for rotating the rotatable member.

8. A cam structure of the character described comprising a pair of relatively revolvable cam members,each having complementary opposed raised portions formed thereon, the raised portion of each of the cam members having an inclined and annularly disposed surface which extends through an angle greater than ninety degrees, the surfaces on the raised portions being normally opposed and in contact with one another, and a tension rod extending axially through the cam members.

9. A cam structure of the character described comprising a pair of relatively revolvable cam members, each having opposing raised portions thereon, each raised portion being formed with a plurality of gradually inclined and annularly disposed surfaces which are located one inside another and each of which surfaces extends through an angle greater than ninety degrees, the surfaces on the raised portion of one cam member being adapted to operatively engage with the surfaces on the raised portion of the other cam member.

10. A cam structure of the character described comprising a pair of relatively revolvable cam members, each having complementary opposed raised portions formed thereon, the raised portion of each cam member having an inclined and corrugated annular surface thereon, the surfaces on the raised portions being normally opposed and in contact with one another, a handle on one of the cam members, and a tension rod extending through the cam members, the said tension rod having a head in engagement with the particular cam member provided with the handle.

11. A cam structure of the character described comprising a pair of relatively revolvable cam members, each having opposing raised portions 325 formed thereon, each raised portion being formed with a plurality of gradually inclined and annularly disposed surfaces which are located one inside another, the highest point of one surface being located opposite the lowest point of its adjacent surface, the surfaces on the raised portion of one cam' member being adapted to operatively engage with the surfaces on the raised portion of the other cam member.

CASS T. WALKER. 

